Cerebral amyloid angiopathy, also known as congophilic angiopathy, is a form of angiopathy in which amyloid deposits in the walls of the blood vessels of the central nervous system.
The term congophilic is used because the presence of the abnormal aggregations of amyloid can be demonstrated by microscopic examination of brain tissue after application of a special stain called Congo red.
An immune mechanism has been proposed.
Amyloid deposition predisposes these blood vessel to failure, increasing the risk of a hemorrhagic stroke
. Because can be caused by the same amyloid protein that is associated with Alzheimer's dementia such brain hemorrhages are more common in people who suffer from Alzheimer's, however they can also occur in those who have no history of dementia
. The hemorrhage within the brain is usually confined to a particular lobe and this is slightly different compared to brain hemorrhages which occur as a consequence of high blood pressure (hypertension
) - a more common cause of a hemorrhagic stroke (or cerebral hemorrhage
Susceptibility weighted imaging
has been proposed as a tool for identifying microhemorrhages.
Biopsies also play a role in diagnosing the condition.
It is usually associated with amyloid beta
. This form has been associated with "Abeta-related angiitis
However, there are other types:
- the "Icelandic type" is associated with Cystatin C.
- the "British type" is associated with ITM2B (also known as "BRI").